This invention relates to the production of articles from plastic foam and in particular to the production of foam articles having curved surfaces which may bear a coating of functional or decorative utility.
The most common form of foam production is to form webs or blocks of foam which may have a wide range of widths and thicknesses. Shaped foam articles may be fabricated from the foam webs by cutting, folding, compressing or adhering one or more sections of foam web. Shaped foam articles may also be produced by forming the foam in situ in a mold. However, these techniques are not practical for the commercial production of elongate strips, particularly those having a length of several meters or more.
Foam articles having curved surfaces have been produced by cutting or sculpturing a foam web or block. They have also been produced by shaping a first foam web by folding or compression (e.g., in a mold) and adhering a second foam web or other substrate to the shaped foam, thereby preventing the shaped foam from returning to its original form. The adhering step can be carried out using an adhesive or welding, e.g., by application of heat or ultrasonics. An example of such a shaping technique is disclosed in U.S. Pat. No. 4,740,256 which discloses a process for making elongate weather strips.